oooh thanks very much! i am pleased with the idea, and this was the first idea i had with my little bucket of leds lol, and i tried very hard to vary the colours, there is some that actually change colour during the shot

well there is a slide at night, put the camera at the bottom with a slow shutter of about 30 seconds. take little button batteries, attach different coloured LEDs and throw them at the slide that is the result